TAMPA — It’s all eyes on the refurbished ballpark and recovered ace when the Mets open their 2012 season today against the Braves.

Will Citi Field’s smaller dimensions help hitters such as David Wright and Jason Bay regain their power stroke, or will Mets pitchers suffer? What about ace Johan Santana, who hasn’t pitched in 19 months?

After trimming the payroll back from $140 million to $90 million and with questions littering the roster, the expectations are lower for the Mets this year than any in recent memory, with many pundits forecasting a last-place finish in the NL East.

Starting today, the Mets will begin to show if they are a disaster-in-waiting, a scrappy club that can stay in the playoff chase deep into the summer, or if they are something in between.

Santana will throw the initial pitch of the team’s season — and his first in a regular season game since Sept. 2, 2010 — officially putting a turbulent Mets spring training in the rearview.

The Mets obviously value Santana’s left arm, but that is only part of the entire package.

“He’s borderline insane, and when he’s around it just loosens everybody up,” Wright said yesterday.

As for the ballpark, the Mets are hoping shorter fences in left and right field will make baseball in Flushing more entertaining, perhaps invigorating Wright and Bay in the process. No longer in play is the 17-foot fence in left that turned many homers into doubles. Also gone is the cavernous “Mo’s Zone” in right.

The Mets changed the configuration of a practice field at their spring training complex to emulate the new Citi Field, but the players want to see the real thing to believe.

“You can change the chain links all you want on Field 7, but when you’re still in Florida, you take BP and the wind is howling and it’s a completely different feeling,” Bay said. “It will be interesting just to see the first few days how it plays, not just hitting wise, but defensively and pitching wise.”

Wright downplayed the idea of a “new” Citi Field.

“It’s just minor adjustments,” he said. “I’m sure I’ll remember where to park. I’m sure I’ll remember where the clubhouse is, so that’s the important thing.”

Still unanswered is whether the Mets will get an Opening Day sellout. As of Monday, “several thousand” tickets remained unsold according to a team official. It could leave the Mets with their first non-sellout of a home opener since 1997.

“It wouldn’t be a downer for us, but it would be unfortunate,” Josh Thole said, referring to the possibility of a non-sellout. “But as far as us, how we prepare, it doesn’t change anything. It’s still going to be a great time. The fans that are there are going to be into it.”

The Opening Day ceremonies will include the team honoring Gary Carter, the catcher on the 1986 championship team who died from brain cancer in February.

Santana survived the entire spring training after missing all of 2011 recovering from surgery to repair a torn anterior capsule in his left shoulder, but Wright, Andres Torres and Tim Byrdak missed significant stretches. Ruben Tejada also was sidelined for a short stretch.

Yet the Mets have arrived at Opening Day with their entire starting lineup, rotation and bullpen intact.

“We’re very fortunate,” Wright said. “The medical staff gets crushed a lot, but I think they deserve a lot of credit for getting guys back on the field.”

Manager Terry Collins plans to keep Santana on an 85-90 pitch count today. The veteran lefty had body soreness last week, but had a solid bullpen session on Saturday to convince team brass he is ready.

“Obviously, we’ve got the big boy going and that means a lot,” Collins said. “That’s an exciting time for everybody to see him on the mound again.”